The CV631 (commercially the 828) is a transmitting pentode of 80 Watts dissipation. As an RF output valve in constant commercial service the output can be 300 Watts. The filament is thoriated tungsten.
A pair can also be used in Class AB1 as an audio modulator.
The screening allows little more on display than the graphite anode and ceramic insulators.
The remains of the commercial 828 Type designation.
The graphite anode and close-wound suppressor grid.
The top ceramic insulator holding the filament tension springs. The anode connection to the top cap is via a pair of tapes.
The suppressor grid seen from the top.
The wide glass tube envelope is 50 mm in diameter and, excluding the UX5 base pins, is 178 mm tall.
Reference: Data-sheet. Type CV631 was first introduced in 1939. See also1939 adverts.
